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《化学工业与工程技术》2020,(1):1-5
采用一步水热法,在乙二胺的辅助下,制备了硫化钴/石墨烯气凝胶(CoS/GA)复合材料。通过X射线衍射法(XRD)、扫描电镜(SEM)、电化学性能测试对材料进行了表征和测试。结果表明:制备的材料晶型规整,30~100 nm的CoS粒子均匀地分布在石墨烯气凝胶上。用作超级电容器时,在电流密度0.5 A/g时,CoS/GA复合材料比电容值达574 F/g,是纯CoS的1.4倍;充放电循环1 000次后,比电容保持率为94.4%。硫化钴/石墨烯复合材料的电化学性能较好,具有较大的比电容和较好的循环稳定性,是一种可用于超级电容器的较有潜力的电极材料。 相似文献
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石墨烯作为一种具有独特二维结构的新型无机纳米材料,因其优异的力学、热学、电学和光学性能,使其成为应用在电化学领域的理想材料。详细综述了石墨烯基复合材料的各种制备方法,并对其在超级电容器中的应用现状进行了系统总结。 相似文献
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采用一步水热法制备石墨烯纳米片(GNS)/CoS2复合材料,利用XRD和SEM对所制备复合材料的微观结构进行表征,采用循环伏安法和交流阻抗法对复合材料的电化学性能进行研究。研究结果表明,在水热过程中,氧化石墨(GO)逐渐被还原成石墨烯纳米片(GNS),能够为CoS2晶核的形成提供更多的接触点,有利于CoS2颗粒均匀地生长在GNS表面。这种结构的复合材料既能够显著增加CoS2和电解液之间的有效接触面积,提高CoS2的电化学利用率,同时又能够改善材料的导电性,有利于提高材料的比电容。 相似文献
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采用一步水热法制备石墨烯纳米片(GNS)/CoS2复合材料,利用XRD和SEM对所制备复合材料的微观结构进行表征,采用循环伏安法和交流阻抗法对复合材料的电化学性能进行研究。研究结果表明,在水热过程中,氧化石墨(GO)逐渐被还原成石墨烯纳米片(GNS),能够为CoS2晶核的形成提供更多的接触点,有利于CoS2颗粒均匀地生长在GNS表面。这种结构的复合材料既能够显著增加CoS2和电解液之间的有效接触面积,提高CoS2的电化学利用率,同时又能够改善材料的导电性,有利于提高材料的比电容。 相似文献
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分析了目前石墨烯和聚吡咯(PPy)用作电极材料的不足,详细介绍了近年来超级电容器用石墨烯/PPy复合电极材料的研究进展,指出石墨烯/PPy复合材料在能量转换和存储领域的未来发展方向. 相似文献
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Hossein Pahlavani Javad Shabani Shayeh Amideddin Nouralishahi Maryam Sharifi Paroushi 《应用聚合物科学杂志》2024,141(3):e54812
This research studies the improving effects of graphene porous (GP) on the supercapacitive performance of a polyaniline/graphene porous (PANI/GP) nanocomposite. GP nanosheets were synthesized via chemical vapor deposition, and PANI/GP was electrochemically composited through successive cyclic voltammetry. The samples were characterized by fast Fourier transform infrared (FTIR), x-ray diffraction (XRD), and scanning electron microscopy (SEM), and energy-dispersive x-ray spectrometry (EDS) techniques. Porous GP nanosheets were uniformly dispersed in the composite structure. Furthermore, the electrochemical performances of the synthesized samples were compared using galvanostatic charge/discharge, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). Incorporating GP into the PANI significantly increased specific capacitance from 276 (in PANI) to 577 F/g (in PANI/GP). The electrochemical stability of electrodes was compared during 1000 successive charge/discharge cycles. After 1000 cycles, PANI/GP kept 90% of its initial capacitance, and only 25% of the charge storage capacitance of bare PANI remained. 相似文献
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《Ceramics International》2019,45(15):18247-18254
Three-dimensional (3D) porous LiFePO4/graphene aerogel (LFP/GA) composite was successfully prepared by an in-situ hydrothermal process. In this composite, the LiFePO4 microspheres assembled by nanoparticles were embedded in a three-dimensional framework intertwined with the graphene sheets, which acts as a bridge for transfer of electron and diffusion of lithium ion. The large specific surface of the composite structure enables the increased infiltration area and utilization of the active material. The content of the graphene sheet is analyzed and is found important for the Li-storage characteristics of LiFePO4. An aerogel composite with 10% of graphene displays the best electrochemical performance, with the specific discharge capacities of 168 mAh g−1 and 155 mAh g−1 at respectively 0.1C and 1C, and the capacity retains 96.3% for up to 800 cycles. This novel 3D porous aerogel composite is identified as a promising cathode material for the rechargeable Li battery, and the simple strategy may be applied to construct other high performing composite structure and materials. 相似文献
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《Ceramics International》2016,42(10):12097-12104
In this work, cross-linked graphene aerogel (CL-GA) and its composite with Fe2O3 nanoparticles (NPs) were synthesized through a one-step hydrothermal procedure by using p-phenylenediamine (PPD). Structural characterizations revealed that in the preparation of the composite PPD acts as a cross-liker and provides high surface area by decreasing restacking of graphene sheets and functions as nitrogen source simultaneously. The electrochemical characteristics of the nanocomposite were investigated by cyclic voltammetry (CV), galvanostatic charge/discharge, electrochemical impedance spectroscopy (EIS) and Fast Fourier transform continues cyclic voltammetry (FFTCCV). The results show that cross-linked graphene aerogel/Fe2O3 (CL-GA/Fe2O3) nanocomposite displays enhanced supercapacitive performance, where it has capacitance of 445 at 1 A g−1, high energy density of 63 W h Kg−1, and 89% capacitance retention after 5000 cycles in 3 M KOH. Presence of PPD considerably improved supercapacitive performance of nanocomposite as a result it could be promising material in synthesis of efficient graphene/metal oxide-based electrode material for high performance supercapacitors. 相似文献
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石墨烯是由单层碳原子紧密堆叠而成的蜂窝状材料,具有比表面积大、传热性能好、导电能力强等优点,普遍应用于各个领域。但由于石墨烯使用过程中易团聚,导致其应用领域受限。石墨烯组装而成的3D石墨烯拥有更大的活性表面积等特性,近年来引发密切关注。与此同时,石墨烯、3D石墨烯改性成为当前探究的焦点。本文在介绍石墨烯、3D石墨烯的结构、性能及石墨烯制备的基础上,总结了3种复合材料的主要制备途径,并且分析了其合成方法的利弊。重点探讨了它们在锂离子电池、燃料电池的电化学催化剂及传感器中的应用,简述了复合材料优良性能产生的机理。提出在掺杂改性中应注意各元素掺杂量、掺杂比例、掺杂位点的确定等问题。最后指出了石墨烯、3D石墨烯及其复合材料的制备还面临不稳定、无法大规模生产、导电率低的瓶颈并对其在固态金属锂电池、透明电池、吸附材料等领域的发展前景做了展望。 相似文献